Sindarin: Núrnen ‘Sad-water(s)’ (as also known in English, German)
English: Sea of Nurn
German: Binnenmeer Núrnen ‘Sea of Nurn’
References:
Verified:
Sea of Núrnen
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Núrnen / Lake Núrnen,
Mordors inland sea.
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Núrnen / Sea of Núrnen,
Mordors great inland sea.
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